1. Field of the Invention
The invention relates to a weaving machine transmission.
2. Description of the Prior Art
A weaving machine transmission for a terry cloth weaving machine which permits a modulation of the weft beat-up position of the reed is known from the specification EP 350 446. This weaving machine transmission enables the beat-up movement of the reed to be modulated in such a manner that either a full beat-up or a partial beat-up is carried out. This modulation of the beat-up enables a terry cloth to be produced. Disadvantageous in the known weaving machine is that individual parts such as rollers or control curves are subjected to an extremely intensive alternating stress, which has a rapid wear of these components as a con-sequence.
The object of the present invention is to propose an economically more advantageous weaving machine transmission which is suitable in particular for use as a terry cloth transmission.
The object is satisfied in particular by a weaving machine transmission for the control of the stroke of a sley shaft, comprising a roller lever and a sley shaft between which there is an active connection, with the roller lever and the sley shaft being arranged so as to be pivotal and mutually rotatable about a common axis, with a joint arrangement forming the active connection between the roller lever and the sley shaft, and with the joint arrangement being designed such that the length of the active connection can be varied by means of an adjusting apparatus which acts on the joint arrangement.
A weaving machine usually has a main drive shaft and a plurality of cam or eccenter packages which are arranged on it. The weaving machine transmission in accordance with the invention comprises a roller lever with two rollers, with the rollers rolling along the eccenter package so that the roller lever continually executes a pivotal movement. A sley is also firmly connected to the sley shaft. The weaving machine transmission in accordance with the present invention permits the sley shaft, or the position of the sley with respect to the position of the roller lever, to be pivoted. Through this the final position or the reversal point of the sley respectively is in particular adjustable, so that either a full beat-up or a partial beat-up is possible with the sley. The joint arrangement in accordance with the invention forms an active connection between the roller lever and the sley shaft. The joint arrangement is for example designed as a toggle lever. The weaving machine transmission in accordance with the present invention has the advantage that a lower stress arises, which has a lower wear as a consequence. The joint arrangement, which forms the active connection between the roller lever and the sley shaft, is subject to a lower loading and therefore a very low wear, in particular also because the joint arrangement has no components which roll or slide along one another. An adjusting apparatus which acts on the joint arrangement permits the centre of gravity for the joint arrangement to be actuated and thereby the angle between the roller lever and the sley shaft to be adjusted. The adjusting apparatus is preferably designed such that it is possible to modulate the beat-up location of successive movements of the sley, preferably in such a manner that each beat-up location can be set individually and independently of the previous beat-up location. This enables a modulation of the beat-up location of the sley for individual wefts.
In a preferred embodiment the toggle lever is arranged in the joint arrangement in such a manner that the latter is located in an extended position extending in a straight line at least in a full beat-up of the sley, so that the torque which is to be transmitted from the roller lever to the sley can be transmitted ideally, in particular without loss and without a spring action arising. Through this geometrical embodiment the stress during the full beat-up is considerably reduced. The roller lever and the sley shaft are pivotally journalled about a common axis. In an advantageous embodiment the roller lever with its rollers and further components which might be required is designed in such a manner that it has a mass distribution which is substantially symmetrical with respect to the common axis.